Improvement in hoisting apparatus



R. 0'. PEIRCE. HOIS'IING APPARATUS.

No. 195,640, Patented Sept.25,1877.

INVENTOR flw/wzm. WWW

ATTORNEY NFEI'EHS. PNOTO-LITHOGRAPHER. WASHINGTONv D C OFF-10E.

ROBERT o. E-I' oR, on PORTLAND, MAINE.

IMPROVEMENT IN HOISTING APPARATUS.

Specification forming part of Letters Patent No. 195,640, dated September 25,1877 application filed August 11, 1877.

To all whom it may concern Be it known that I, ROBERT O. 'PEIROE, of Portland, in the county of Cumberland and State of Maine, have invented a new and valuable Improvement in Hoisting Apparatus; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, and to the letters and figures of reference marked thereon.

Figure 1 of the drawings is a representation of front view of my invention. Fig.2 is a longitudinal vertical section thereof, and Figs. 3 and 4 are details.

This invention has relation to improvements in hoisting-machines; and it consists in the arrangement and novel construction of the various devices used, as will be hereinafter more fully set forth and claimed.

In the annexed drawings, the letter A designates a strong metallic frame, having parallel sides and rounded ends, provided each with a vibrating hook, or. This frame affords bearings for three transverse metallic shafts, B G D. The I shaft B is provided, outside of the frame, with a master or power wheel, E. and between the latter and frame with a ratchet-wheel, F. It has also an inside gear-wheel, F, that engages a large gear-wheel, G, on the shaft 0. This latter has upon its outer end a pinion, H, that meshes with a large gearwheel, I, upon the outer end of the shaft D, which is provided with the chain-wheel J.

Itis evident that by rotating the power-wheel power will be transmitted to the chain-wheel through the various gears and shafts.

The frame is suspended from any suitable support by means of its upper hook a. The hoisting-chain is then secured to its lower hook on, extended through ahook-block, Z, to which the object to be lifted is secured, and is then passed up over the chain or rag wheel J.

Fig. 1 shows the pinion H of small diameter, and the gear-wheel comparatively very large. The gear-wheel actuating this pinion is large, and the gear-wheel upon the shaft of the power-wheel E comparatively small, by which means the greatest possible power is obtained, but with corresponding loss of speed.

The pinion H and gear-wheel I are removable from their respective shafts, and interchangeable with each. By shifting the gearwheel to the pinion-shaft and the pinion to the gear-wheel shaft a great increase of speed is obtained in raising substances, with a corresponding loss of power, thus adapting the machine to the rapid elevation of light weights.

M N designate a pinion and gear-wheel of medium size, the former of greater diameter than pinion H, and the latter of less diameter than the gear-wheel 1, whose places they are designed to take in raising moderately heavy weights at a comparatively high rate of speed.

I have thus constructed a machine that is adapted to be used with advantage in raising heavy, light, and medium weights.

The backward rotation of the power-wheel and the mechanism actuated thereby is prevented by means of a pawl, L, engaging the ratchet-wheel F, and held into engagement therewith by means of a suitable spring, S.

P designates a spring-brake, one end of which is rigidly bolted to the frame just below the level of the shaft. It then passes under and around said shaft, and terminates in a lever-handle, Q.

R represents a chain passing up through the loop q, and provided above said loop with branches r r, secured the one to the leverhandle and the other to the pawl. By draw ing down upon the chain B when the load is at the desired height, the pawl will be disengaged from the ratchet-wheel F and the looped portion a of the brake caused to bind upon the shaft of the power-wheel E, thus preventing the load from coming down by the run.

The frame may be made in two sections, '11 i, securely bolted, or otherwise secured together, if I so elect.

What I claim as new, and desire to secure by Letters Patent, is-

1. The combination, with the frame A, having shaft B, power-wheel E, and gear-wheel F, and the shaft 0, having the fixed gearwheel G and removable pinion H, of the shaft D, having the chain-wheel J and removable gear-wheel I, engaging said pinion H, substantially as specified.

2. The combination, with the driving-shaft B of a hoisting mechanism, having the ratch- In testimony that I claim the above I have et-wheel F and a spring-actuated pawl enhereunto subscribed my name in the presence gaging said ratchet, of a brake, P, secured at of two witnesses.

one end to the frame, then looped around the said driving-shaft, and extended beyond the ROBERT PEIRCE' same to form a handle, Q, and a chain, R, hav- Witnesses: ing branches 1' r secured, respectively, to the GEO. F. ALEXANDER,

brake and pawl, substantially as specified. Z. K. HARMON. 

